Riot police break up anti-pope demo near Santiago mass

Anti-riot police used water-cannon to disperse hundreds of people protesting sexual abuse by priests as they tried to disrupt an open air mass by Pope Francis in Santiago on Tuesday.

Police moved in on the demonstrators as they headed towards the city's O'Higgins Park, where Francis was presiding over a huge open-air mass for some 400,000 pilgrims on the first day of his visit to the South American country.

Police used armored vehicles to fire water cannon at the demonstrators and arrested around 50 people, bundling them into vans.

Many of the demonstrators chanted "pedophile accomplices" as they approached the park.

A man dressed as the pope and two other people dressed as nuns unfurled a banner from the balcony of a nearby building that read: "Francis, accomplice of pedophile crimes."

Other demonstrators walked under a banner saying, "The poor of Chile are marching"

Francis' visit -- his first to Chile as pope -- has been overshadowed by a report outlining the depth of sexual abuse in the local Church, and his appointment of a bishop who many here believe covered-up the country's most prominent sex abuse scandal.

The US-based NGO Bishop Accountability said ahead of the visit that almost 80 Roman Catholic clergy members had been accused of sexually abusing children in Chile since 2000.